<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
	<title></title>
	<style type="text/css">
		*{
			margin: 0;
			padding: 0;
		}
		.box{
			width: 90%;
			height: 200px;
			line-height: 200px;
			margin: 0 auto;
			overflow: hidden;
			text-align: center;
		}
		.box div{
			width: 33.3%;
			height: 100%;
			background: gray;
			float: left;
		}
	</style>
</head>
<body>
   <div class="box">
   	   <div class="left">左</div>
   	   <div class="middle">中</div>
   	   <div class="right">右</div>
   </div>
</body>
</html>